55. There are many children and adults whom behavior is generally unacceptable.

解析：有很多孩子以及成人的行为普遍不被接受。

孩子以及成年人的行为，behavior前面应该用表示所有格的whose，相当于one’s，在本句中是children and adults’ behavior，而不应该用宾格whom。正确的句子应该是There are many children and adults whose behavior is generally unacceptable.